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I had hoped that using Dimension Engineerings DE-SW050 switching regulator to power my airborne camera (PAL) and transmitter would solve the problem of the heat generated by a linear regulator (I am drawing 0.5A at 5v). Unfortunately they result in patterning on the video signal even if I mount them away from the transmitter and camera.

Has anyone any suggestions or are switchers just not compatible with wireless video?

regards Peter

ps I am using a diversity system and was hoping to use a similar regulator to power the two receivers but again that seems problematic.

Edited by pseddon

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The pattern noise is from the excessive ripple on the DC-DC switcher. I have found that it affects both the camera and the Tx. It can even cause reduced satellite locks on a GPS Rx.

For the average switcher I suggest LC filters on both the input and the output. Sometimes a linear Vreg with a big heatsink is less work. :)

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Hey Peter. I have experienced the same thing with their 5V regulator. Actually, the video screen capture you see on that page was from one of my flights. If you don't want to add capacitors and stuff, there is another option. They also make an Anyvolt Micro. I have found that it has better control over voltage ripple and have not experienced the video banding at all using it. I'm using the usual KX-131 camera and Lawmate (Rangevideo, Future Hobbies, etc.) 500 mW transmitter. And the nice thing about it is it's a step up/step down adjustable regulator. Don't power any more than the camera and Tx though, as it can only handle about 500mA.

Brian

Edited by twinturbostang

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Peter,

I've had good luck with the DE 5V reg and a KX-141 cam. I added a resistor to the cam (as recommended by BlackWidowAV) and the banding disappeared. The anyvolt micro is a good option too as Brian suggested. I can confirm that it does heat up if you push it, while the 5V reg stays cool.

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docphi, what kind of resistor is that (value, where to connect)? I've just looked over blackwidowav website and found nothing. Could you please provide some details?

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If it's the "resistor" BWAV supplies with the 141, it's actually an inductor :)

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I dont' have BWAV gear but some other camera, which suffered from switching p/s noise. I actually solved it with low drop lin reg but just would like to know the resistor trick so I have more options when I encounter similar thing again.

Do you mean this is an inductor you connect in series on Vcc line? What is the inductor's rating?

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I tried an LC filter on the input and output of the switching regulator and it made a considerable difference on the output side . Being short of L's I wasn't able to try different values. However there was still some very slight interference on sharp edged dark to light transitions and in some of the solid colours so I've gone back to a linear and reduced from 3 to 2 cell LiPo.

Thanks for the help.

regards Peter

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However there was still some very slight interference on sharp edged dark to light transitions and in some of the solid colours so I've gone back to a linear and reduced from 3 to 2 cell LiPo.

Do you have a video sample we can see? Some of that may not be "interference" and just the nature of the camera.

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